Presently fluid spray systems such as paint spray guns, guns for spraying internally mixed fluids and other types of fluid delivery spray systems employ solvents for cleaning the systems after use. The purging fluids presently used are a variety of fluids which have high vapor pressures and often are either toxic or highly flammable. Examples of such fluids are acetone, methyline chloride and ketone compounds. Of the ketone compounds, one type of compound called methylethyl ketone (MEK) is widely used as a solvent. The problem with these solvents is that they have high vapor pressure and can be pollutants. Environmental agencies are increasingly cracking down on the use of these fluids with federal, state and local agencies restricting their use and disposal. Some of the solvents, like acetone, are high volatile organic compounds (VOC). They're are extremely flammable compounds and have low flash point.
Generally these compounds are used to purge paint or organic compounds from spray guns or systems. The solvent is forced through the internal mixing chambers of the gun immediately after use to discharge any paint or organic compounds which could solidify and clog the gun. These solvents are generally applied to the gun under pressure, and their high vapor pressure makes them undesirable toxic pollutants. There is a trend to get away from the problems of these toxic chemicals because of increasing restrictions by regulatory agencies.
It is, therefore, one object of the present invention to provide a purging system for fluid delivery systems which avoids the use of volatile organic compounds which have high vapor pressures or are highly flammable.
Yet another object of the present invention is to provide a purging system for fluid spray or delivery systems which uses solvents that can easily be disposed of after use without any danger of pollution.
Yet another object of the present invention is to provide a purging system for fluid delivery systems which uses liquids that can be simply poured into sewer after use.
Yet another object of the present invention is to provide a purging system for fluid delivery systems which can be switched from a cleaning fluid, to an air-blow down to eliminate the purging fluid after use.
Still another object of the present invention is to provide a purging system for cleaning lines and mixing chambers of fluid delivery systems which delivers an emulsifying agent under pressure which can be quickly switched to purging air.